The word agora is Greek, meaning market place. Agoraphobia, literally fear of the market place, means fear of open spaces, of outdoors. People with severe agoraphobia will refuse to leave their homes. Other types of phobia can be about virtually anything. Many people have some degree of acrophobia, fear of heights. Many people have xenophobia, fear of strangers. But there are endless types of phobias.
The opposite of agoraphobia is claustrophobia, which is the fear of being in confined or restricted spaces. Agoraphobia involves a fear of open or public spaces, while claustrophobia involves a fear of enclosed spaces.
Claustrophobia (from claustrum "a shut in place")
agoraphobia....
Claustrophobia is considered to be the opposite of agoraphobia. Claustrophobia is the fear of being indoors or in a tight and compacted space. Agoraphobia is the fear of being outdoors and in an open and spacious space.
Claustrophobia is a noun. It's a fear of small or confined spaces.
You are asking for the opposite of claustrophobia which people mistakenly think is agoraphobia which translates, "fear of the marketplace" but it really means that the person is afraid of having a panic attack or being trapped in an embarrassing situation without any escape. I don't believe there is an actual word to describe what the opposite of claustrophobia is. (I googled it and came up with chasmophila which supposedly ment the love of small places but ended up being a fake word)
The phobia of outerspace is called Spacephobia. There are also phobias for confined space (claustrophobia), open spaces (agoraphobia), and empty spaces (cenophobia).
The fear of going out into open spaces or public places is Agoraphobia. People suffering from Agoraphobia are usually known as shut-ins, seldom if ever, leaving their homes, and often this condition is combined with hoarding.
Claustrophobia is the fear of tight spaces. Agoraphobia is the fear of being in crowds. The root word agora actually comes from the Greek for "market place."
It generally falls under Claustrophobia. It can also be classified as Agoraphobia, which is not the fear of open spaces (as is the common misconception). Agoraphobia is defined as the fear of being in a place that is hard to get help in and escape from. Fears of lifts, tunnels and small rooms come under this. This I know because I have a fear of tunnels.
Although there is no term for the fear of basements, in most cases it is a symptom of either Claustrophobia or Agoraphobia.
Claustrophobia